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[Bug rtl-optimization/33673] [4.3 Regression] ICE in verify_flow_info, missing barrier, when multiple tree opts disabled



------- Comment #4 from jakub at gcc dot gnu dot org  2007-10-11 16:27 -------
If cprop_jump changes a conditional jump into unconditional, then it forgets
to add a BARRIER after it.  When not in cfglayout mode that's enough, but
in cfglayout mode it is uglier, though I haven't found a cfg hook which would
do what cprop_jump needs.


--- gcc/gcse.c.jj  2007-10-03 21:33:54.000000000 +0200
+++ gcc/gcse.c      2007-10-11 18:13:45.000000000 +0200
@@ -2853,6 +2853,14 @@ cprop_jump (basic_block bb, rtx setcc, r
       /* Remove REG_EQUAL note after simplification.  */
       if (note_src)
        remove_note (jump, note);
+
+      if (any_uncondjump_p (jump)
+         || (returnjump_p (jump) && !any_condjump_p (jump)))
+       {
+         rtx barrier = emit_barrier_after (jump);
+         if (current_ir_type () == IR_RTL_CFGLAYOUT)
+           bb->il.rtl->footer = unlink_insn_chain (barrier, barrier);
+       }
      }

 #ifdef HAVE_cc0

is ugly, but fixes this bug.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33673


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